Bulk acoustic wave (“BAW”) gyroscope use has increased in recent years. This trend is driven by their many benefits including, among other things, their high gain factor, which causes them to use less power than conventional gyroscopes. In addition, such gyroscopes generally cost less to manufacture.
To those ends, many bulk acoustic wave gyroscopes known to the inventors have a disk with a crystal lattice that, during either or both an actuation or detection phase, vibrates/resonates at a very high frequency, typically in the megahertz range. This is in contrast to gyroscopes having a disk mechanically moving back and forth about a substrate in both phases. When the crystal lattice of the disk vibrates, the disk is considered to be operating in a “bulk” mode.
To provide support, the disk of a BAW gyroscope is anchored to and suspended above a base substrate. When subjected to certain motion (e.g., a rotation), the shape of the disk changes in a known manner. Circuitry detects this change in shape to provide the information of interest, such as the amount and type of motion detected.